[hpsdr] Predistortion and different types of amplifiers?

[John Marvin]

I was planning on either building Helmut's design or purchasing a RF-S2K 
sampler from cleanrf.com (one man company located in my home town, so I 
thought I might help him out and save the time of putting something 
together myself). However, both of these samplers require a break in the 
signal path, which is probably more modification than I want to do to my 
amp at this point.

I haven't actually looked, but I believe the interface you are talking 
about is not a plug on a cable that I could easily unplug and put 
something in the path, but is instead a plug on a board that is attached 
directly to a jack on an adjacent board on the board stack, requiring a 
more significant and permanent (albeit probably not difficult) change to 
a product under warranty.

I am still interested to know what the tradeoff will be with including 
the tuner in the path.

Thanks Lyle for sharing this information regarding the KXPA100. I might 
first see how well PureSignal performs, even if I have to recalibrate 
with every tuner change, and then decide if I want to pursue a better 
connection option.

John
AC0ZG

On 2/12/2014 3:31 PM, Lyle Johnson wrote:
> John,
>
> I am not sure what the rf sampler looks like, but you can tap the RF 
> from the KXPA100 PA to the KXPA100 ATU at the P8<->J8 interface in the 
> board stack.
>
> Pins 1-4 are the RF, pins 5-6 are ground.
>
> 73,
>
> Lyle KK7P


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